The crossword solutions for the term 'ruin, as plans' are 'derail' (6 letters) and 'TORPEDO' (7 letters). Derail is a verb meaning to cause something to go off track or to prevent something from happening as planned. It is often used in the context of a train being derailed, but can also be used to describe any plan or project that has been disrupted. TORPEDO is a noun meaning an explosive device that is launched underwater to destroy ships or submarines. It is often used figuratively to describe an action that disrupts or destroys a plan or project.